This invention relates to concrete forming systems and more particularly to an improved concrete forming system for monolithic pouring of foundation footers and upright walls of concrete structures which include limited width and height adjustments for the foundation footer.
Conventional concrete foundations and upright walls have heretofore been erected with the use of forms built from lumber and plywood material Typically, such concrete structures are formed in two parts with the footer being poured separately from the wall. A waterproofing membrane is normally installed between the footer and upright wall to form a watertight structure. This method is very expensive due to the high cost of lumber and labor to erect and remove the temporary forms once the footer and upright wall is poured and hardened.
Oftentimes, jobsite field changes to the foundation footer are required due to unknown elements in the terrain and other circumstances. Conventional wood forms can be changed on the jobsite to compensate for field changes and unknown terrain elements. However, form systems which utilize pre-manufactured or factory made welded wire reinforcing grids members are not easily changed in the field to compensate for such unknown elements that arise on the jobsite. U.S. Pat. No. 4,972,646 discloses such a form system where predetermined width welded wire grid members are positioned between stay in place insulated panels of an upright wall and footer form. While these systems provide insulation for the concrete structure and can be left in place, thus eliminating the expense of temporary form removal, they are lightweight and require knowledgeable labor to assemble correctly so that wall height and thickness and footer size and location can be properly controlled to reduce form uplift and lateral movement during pouring. To change in the field any dimensions of the foundation footer formed with this type system requires changing the dimensions of the stay in place panels and the premanufactured hooked end rods which extend between the panels.
Other inventions have been developed to reduce some of the above problems. U.S. Pat. No. 5,040,344 discloses a stay in place form system for insulated upright walls which utilizes superimposed polystyrene panels, horizontal stiffeners and fixed length hooked rods to form upright concrete walls of a thickness determined by the length of the hooked rods. When reinforcing rods or concrete reinforcing wire is required in the wall formed by this type system, excessive time and effort is required to assemble the insulated panels and horizontal stiffeners in place while connecting the fixed length hooked rods through the reinforcing rods to the horizontal stiffeners.
U.S. Pat. No. 3,881,291 discloses a panel mold for forming composite concrete reinforced walls. This system utilizes fixed length rods extending between spaced apart upright stay in place panel members with the ends of the rods anchored in place with bonding material. Due to the light weight material utilized for the walls, the thickness of the concrete wall capable of being formed by this system is limited to approximately 6 inches Any field changes to the foundation footer formed by this system would require additional labor to change the length of the fixed length rods and the dimensions of the stay in place panels utilized with system